Composition for fire-proof paper or board



(No Model.) v J. G. MERRILL.

GOMPOSITIONFOR FIRE PROOF PAPEROR BOARD. No. 424,328. Patented Mar.'25, 1890.

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UNIT D STATES PATENT OFFICE.

JONATHAN G. MERRILL, OF QUINCY, MASSACHUSETTS.

COMPOSITION FOR FIRE-PROOF PAPER OR BOARD.

SPECIFICATION forming' part of Letters Patent No. 424,328, dated March 25, 1890.

Application filed November 20, 1888- Serial No.2 91,3l8. (N0 specimens.)

To all whom it may concern:

Be it known that I, JONATHAN G. MERRILL, a citizen of the United States, and a resident of Quincy, in the county of Norfolk and State of Massachusetts, have invented new and useful Improvements in Compositions for Making Fire-Proof Paper or Board, of which the following, taken in connection With the accompanying drawings, is a specification.

This invention has for its object to improve the compound for making fire-proof paper or board described in the Letters Patent issued to me May 31, 1887, No. 363,905, whereby the efficiency of the paper or board is increased.

The improvementis hereinafter described, and specifically set forth in the claim.

-I prefer to use in making the paper or board a composition comprising forty per cent. of Vegetable or pinged fiber, or both; fifteen per cent. asbestus; ten pe cent. alum or copperas, or their equivalents-such as, for instance, salt or tungstate of soda; ten per cent. plumbago, lamp-black, or other suitable coloring material, and twenty-five per cent. infusorial earth. To every five hundredpounds of the above mixture is added about one hundred pounds of silicate of soda, and the composition is thoroughly mixed with Water in an ordinary pulp or paper ma chine, and is then run through an ordinary paper-mill into the form of paper or board. After being dried, one or both surfaces of the paper or board are treated With a layer or 2 represents it as coated on one of its surfaces with a layer or coating of silicate of soda or other fire'resisting material, and Fig. 3 is a view showing both of its surfaces coated with silicate of soda or other fire-resisting material.

In the drawings, A represents the board or paper before it has been treated with coating of the silicate of soda a a (shown, respectively, on one side of the board in Fig. 2 and on both sides in Fig. 3.) By reducing the percentage of vegetable fiber and adding infusorial earth the fire-resisting property of the board or paper is materially increased, renderingit particularly well adapted for covering or lining floors,walls of vaults, rooms, or apartments generally. It is also useful for a great many other purposes, such as protection of shutters, roofs, &c.

I do not wish to confinemyself to the exact proportions of the ingredients herein specified as forming the composition.

What I wish to secureby Letters Patent, and claim, is-

A composition for making fire-proof paper or board, consisting of vegetable or animal fiber, asbestus, alum, or copperas, a coloringmatter, infusorial earth, and silicate of soda, substantially in the proportions herein set forth.

In testimony whereof I have signed my name to this specification, in the presence of two -subscribing Witnesses, on this 17th day of November, A. D. 1888.

. JONATHAN G. MERRILL. Witnesses:

ALBAN ANDRRN, HENRY CHADBOURN. 

